Unknown2019-08-272019-08-271966-06RPB-103-08-011http://hdl.handle.net/20.500.11867/177603 sheets 8.5 x 11 inch letterhead. Typed. Annotated in pencil. 2 photographs 8.5 x 11 inch. Captions attached.Advertising the product Hydro-Stop "to stop basement leaks due to wall cracks." Includes a photograph of the product in use and a diagram of how it works. Both have captions.Photograph